How to overcome loading chunk failed with Angular lazy loaded modules

Question

If I make changes to my angular app the chunk names will change on build and the old version will be remove from the dist folder. Once deployed if a user is currently on the site and then navigated to another part of the site I get a loading chunk failed error as the old file is no longer there.

My app is built using angular cli so it's packaged using webpack.

Is there anyway this can be overcome.

Answer 1

PWA SOLUTION BELOW

I had the same problem and found a pretty neat solution that is not mentioned in the other answers.

You use global error handling and force app to reload if chunks failed.

import {ErrorHandler, Injectable} from '@angular/core';

@Injectable()
export class GlobalErrorHandler implements ErrorHandler {
  
  handleError(error: any): void {
   const chunkFailedMessage = /Loading chunk [\d]+ failed/;

    if (chunkFailedMessage.test(error.message)) {
      window.location.reload();
    }
  }
}

It is a simple solution and here (Angular Lazy Routes & loading chunk failed) is the article I got it from.

---

EDIT: Convert to PWA

Another solution can be to convert your Angular site to a PWA (Progressive Web App). What this does is add a service worker that can cache all your chunks. Every time the website is updated a new manifest file is loaded from the backend, if there are newer files, the service worker will fetch all the new chunks and notify the user of the update.

Here is a tutorial on how to convert your current Angular website to a PWA. Notifying the user of new updates is as simple as:

import { Injectable } from '@angular/core';
import { SwUpdate } from '@angular/service-worker';

@Injectable()
export class PwaService {
  constructor(private swUpdate: SwUpdate) {
    swUpdate.available.subscribe(event => {
      if (askUserToUpdate()) {
        window.location.reload();
      }
    });
  }
}